The purpose of the Immunology Core is to serve the common technical and scientific needs of the component projects and to enhance scientific interchange and transfer of skills from American to PNG and Kenyan investigators. The major technical functions of the core are to provide the facilities and experienced technical assistant to perform standardized assays for detection of cytokine and antibody production by T and B lymphocytes and basophils. in addition, the core will produce and purify many of the monoclonal antibodies used in the assays which are not commercially available. A centralized location of these assays will help ensure standardization and quality control and aid in the technical refinement of the assays, especially for use in the field. A core laboratory will also facilitate establishment and maintenance of a bank of frozen serum, cryopreserved lymphocytes, and genomic DNA for use in subsequent studies.